1. Field of the Invention
The present invention generally relates to a motor base and, more particularly, to a motor base that is designed to reduce the noise of the motor by reducing the reverberation energy resulting from the vibration of the motor.
2. Description of the Related Art
Referring to FIG. 1, Taiwan Patent No. 1318559 discloses a motor base 7 of a conventional motor that is designed to reduce the reverberation energy resulting from the vibration of the motor. The motor base 7 includes a base plate 71 having a plurality of annular grooves 72. A shaft tube 711 is mounted on the base plate 71 to support a rotating impeller. The annular grooves 72 enclose the shaft tube 711 to reduce the reverberation energy resulting from the rotation of the impeller.
Due to the arrangement of the annular grooves 72 on the base plate 71, the parts of the base plate 71 which form the annular grooves 72 are thinner, resulting in a weaker structural strength of the motor base 7. As a result, when the motor base 7 is mounted with components such as the impeller, a stator or a circuit board, the motor base 7 may not sufficiently support the motor. Disadvantageously, the quality of the motor is poor, and the service life of the motor is shortened.
To solve the problem, China Patent Application No. 201020004026.0 discloses a fan frame 8 that is designed to reduce the vibrational force during operation. The fan frame 8 includes a base plate 81 and a separating portion 82. A shaft-coupling portion 811 is mounted on the base plate 81. The separating portion 82 surrounds the shaft-coupling portion 811 to reduce the vibrational force and noise. The separating portion 82 has a greater thickness than other parts of the base plate 81, achieving a reinforced structural strength of the fan frame 8.
Although the separating portion 82 provides both advantages of strengthening the fan frame 8 along with relieving the vibrational force placed upon the fan frame 8, the ability of the separating portion 82 to reduce the vibrational force is not as effective as the annular grooves 72 of the motor base 7 due to the fact that the separating portion 82 has a greater thickness than the rest of the portions of the base plate 81.
Referring to FIG. 3, Taiwan Patent No. 483658 also discloses a conventional fan frame 9 capable of reducing the vibrational force during operation. The fan frame 9 includes a base 91 and a plurality of bridging members 92. The base 91 is mounted with a shaft tube 911. The bridging members 92 are connected between the base 91 and an outer ring 93. Each bridging member 92 has a bent section 921 capable of reducing the internal and external vibrations of the fan frame 9.
Due to the facts that the bridging members 92 are connected to the outer ring 93 and that the bent section 921 is arranged on a respective bridging member 92, the bridging members 92 are not connected to the base 91 in a secure manner due to the bent sections 921. In addition, since the bent sections 921 are positioned on the bridging members 92 only, the bridging members 92 cannot be arranged on the entire periphery of the base 91. Consequently, the bent sections 921 cannot omnidirectionally reduce the reverberation energy resulting from the vibration of the shaft tube 911.